prove that the speed of light is not exponential?

[boise]

How do you know that the speed of light is constant?<br />Or could it be getting faster or slower?<br />A Constant makes math comfortable...but what if it is getting slower? <br />What effect would that have on the math of physics,life the universe and everything? hehe.<br />thanks

 

[kmarinas86]

Postulate I: The principle of relativity<br />The laws of physics are the same in all inertial frames.<br /><br />Postulate II: The principle of the constancy of the speed of light. The speed of light (in a vacuum) has the same inertial frams.<br /><br />http://en.wikipedia.org/wiki/Speed_of_light#Light-slowing_experiments<br /><br /><font color="yellow">Light-slowing experiments<br /> <br />Refractive phenomena, such as this rainbow, are due to the slower speed of light in a medium (water, in this case).In a sense, any light travelling through a medium other than a vacuum travels below c as a result of refraction. However, certain materials have an exceptionally high refractive index: in particular, the optical density of a Bose-Einstein condensate can be very high. In 1999, a team of scientists led by Lene Hau were able to slow the speed of a light beam to about 17 metres per second, and, in 2001, they were able to momentarily stop a beam.</font><br /><br />http://en.wikipedia.org/wiki/Speed_of_light#Interaction_with_transparent_materials<br /><br /><font color="yellow">On the microscopic scale, considering electromagnetic radiation to be like a particle, refraction is caused by continual absorption and re-emission of the photons that compose the light by the atoms or molecules through which it is passing. In some sense, the light itself travels only through the vacuum existing between these atoms, and is impeded by the atoms. Alternatively, considering electromagnetic radiation to be like a wave, the charges of each atom (primarily the electrons) interfere with the electric and magnetic fields of the radiation, slowing its progress.</font><br /><br />http://physicsweb.org/articles/

 

[boise]

please excuse my ignorance but I do find this fascinating stuff,<br />so if the speed of light can be changed by gravitational force/magnetism(??) how can distances and hence the age of the universe be measured accurately? or is it all just "rough guess work"! or is the influence of the "bending/slowing" force so small as to be negligible? <br />interesting. reminds me of an argument I read somewhere about the very act of measuring something changes the measurement taken...so do scientists actually live by faith?

 

[kmarinas86]

<font color="yellow">so if the speed of light can be changed by gravitational force/magnetism(??)</font><br /><br />Light can bend due to these forces so even if it speed is constant (at the microscopic level), the rate at which it moves forward vector in a particular direction is reduced (zigzagging).<br /><br /><font color="yellow">how can distances and hence the age of the universe be measured accurately?</font><br /><br />By knowing exactly what happens to light when it travels through the intergalactic and interstellar mediums (at the subquantum level).<br /><br /><font color="yellow">or is it all just "rough guess work"!</font><br /><br />The standard methods of obtaining the Age of the Universe are very precise and logical, but the theory itself is either proven or not proven when equation is either derived or not derived from this theory and used to support the theory itself. In other words, maybe the current understanding of the origin of the Universe is very rough and a bit off.<br /><br /><font color="yellow">or is the influence of the "bending/slowing" force so small as to be negligible?</font><br /><br />Perhaps. I've been wondering if scientists really know if that does not apply to light in the interstellar medium. I think it is possible that many of our calculations of star distances are over estimated, but I cannot propose how that would be the case at this moment.<br /><br /><font color="yellow">so do scientists actually live by faith?</font><br /><br />No they live by what they learn. If they are wrong on this part it's an honest mistake, but it doesn't mean they are living by faith. To live by faith is to know "what" but not to seek to know "how" and "why". Science endeavors to answers these questions and therefore is not committed to "blind unquestioning faith." Our level of science is limited by the limits of our technology.<br /><br /><b>new subject:</b><br /><br />http://64.233.1</safety_wrapper

 

[alkalin]

Someone on the forum suggested that due to greater distance from an object, such as the solar system, that the pull of gravity is narrowed due to further distance from it, therefor has a slightly increased effect. Sounds very reasonable to me, but it means we are dealing with more than just the earth and sun. But what do I know?

 

[newtonian]

boise - I am also fascinated by these things.<br /><br />When scientists dogmatically assert a certain model is accurate when it is actually unproven theory, then there is some blind faith involved.<br /><br />Good science does not do that. Bad science does exist.<br /><br />In most cases astronomers seem to be humble and willing to accept increasing light on matters.<br /><br />For example, a recent broadcast on the Science channel chronicled the discovery of the acceleration of expansion of our universe.<br /><br />It turned out that the distance estimates for the supernovae studied were quite wrong, and the adjustments proved acceleration of expansion. Of course, in astronomy distance involves age.<br /><br />On the pioneer anomaly - the answer must address the fact that no such anomaly is observed in the orbiting planets and moons - at least not to my knowledge.<br /><br />Therefore, my conclusion is that the anomaly is related to the fact that the slowing space probes are not gravitationally bound to our solar system.<br /><br />I posted more detail on my theory on another thread over a month ago.<br /><br />I know it sounds counterintuitive.<br />Much longer ago, on the lost SDC threads, borman posted another model indicating the cosmological constant was the cause (he posted it as a possibility, not dogma). <br /><br />Again, the reason why it seemed to operate in reverse to dark energy acceleration was the frame of reference problem.<br />

 

[Saiph]

1) We say the speed of light (in a vacuum of course) is constant, because it is observed to be so. In all our observations of the speed of light, we have found no variation in it. Our measurements are accurate to small fractions of a m/s, so any variation would be easily detectable.<br /><br />2) As for distances:<br /><br />a) Gravitational lensing doesn't do much<br /><br />b) There isn't much out there to slow light<br /><br />c) There isn't much to cause significant zig-zagging<br /><br />d) Current long distance measurement techniques are inaccurate enough in their own right, that A - C are overshadowed. You don't worry about microscopic variations in length when you use a ruler do you? Since we cannot measure accurately enough, these factors are ignored (or rather unimportant, as they don't apply).<br /><br />Now, astronomers are doing studies to see if the speed of light has changed, over billions of years. So the idea isn't ignored. It is, however, firmly confirmed that light is constant now, and has been for quite some time, and is likely to be so for quite some time. <div class="Discussion_UserSignature"> <p align="center"><font color="#c0c0c0"><br /></font></p><p align="center"><font color="#999999"><em><font size="1">--------</font></em></font><font color="#999999"><em><font size="1">--------</font></em></font><font color="#999999"><em><font size="1">----</font></em></font><font color="#666699">SaiphMOD@gmail.com </font><font color="#999999"><em><font size="1">-------------------</font></em></font></p><p><font color="#999999"><em><font size="1">"This is my Timey Wimey Detector.  Goes "bing" when there's stuff.  It also fries eggs at 30 paces, wether you want it to or not actually.  I've learned to stay away from hens: It's not pretty when they blow" -- </font></em></font><font size="1" color="#999999">The Tenth Doctor, "Blink"</font></p> </div>